Extraction of Organonitrogen Compounds from Five Chinese Coals

Apr 20, 2009 - Seven ONCs in F4 from SF coal were detected according to their odd ..... material is available free of charge via the Internet at http:...
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Energy Fuels 2009, 23, 4848–4851 Published on Web 04/20/2009

: DOI:10.1021/ef900086h

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Extraction of Organonitrogen Compounds from Five Chinese Coals with Methanol# Xian-Yong Wei,*,†,‡,§ Xiao-Hua Wang,†, and Zhi-Min Zong†

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School of Chemical Engineering, China University of Mining and Technology, Xuzhou 221008, Jiangsu, China, Key Laboratory of Coal Conversion and New Carbon Materials, Hubei Province, Wuhan University of Science and Technology, Wuhan 430081, Hubei, China, and State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China. †China University of Mining and Technology. ‡Wuhan University of Science and Technology. §Chinese Academy of Sciences. Present address: Department of Chemistry and Chemical Engineering, Xi’an University of Science and Technology, Xi’an 710054, Shaanxi, China. Received February 1, 2009. Revised Manuscript Received April 6, 2009 Heteroatoms in coals, especially nitrogen1 and sulfur, are considered as precursors of contaminator when using coals as fuels. For example, the nitrogen present in coals is emitted as NOx and N2O during combustion, causing acid rain, photochemical smog, greenhouse effects, and ozone-layer depletion.2-4 The predominant source of NOx and N2O emissions is thought to be the nitrogen bound in the organic structures present in all coals.5 Extensive investigations on the structures of organonitrogen compounds (ONCs) in coals have been performed to find out some effective approaches to nitrogen removal from coals.2,6 However, most of the investigations trying to understand ONC structures in coals by inseparable methods could not identify the structures of ONCs in coals at the molecular level. On the basis of a number of experiments, we established an approach to identify organic compounds in coals by a separable and nondestructive method, including fractional extraction and gas chromatography/mass spectrometry (GC/MS) analysis. Such an analysis provided the first molecular-level determination for organohalogens in coals,7 an oxidized coal,8 and hydrotreated coal residues.9 Here, we report our preliminary results about identification of ONCs in five Chinese bituminous coals by such a method.

The five Chinese coals were collected from Longkou (LK), Pingshuo (PS), Shenfu (SF), Getting (GT), and Datong (DT) coal mines, respectively, and pulverized to pass a 200 mesh sieve (